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                                                                   EXHIBIT 10.48

                               NOVATION AGREEMENT

         THIS NOVATION AGREEMENT (the "Agreement") is made effective as of 21st
day of March, 2003, by and among Grant Geophysical, Inc., a corporation
organized and existing under the laws of the State of Delaware (the "Parent
Company"); Grant Geophysical (Int'l), Inc., a wholly-owned subsidiary of the
Company, organized and existing under the laws of the State of Texas (the
"Subsidiary Company"); and Richard J. Dunlop (the "Employee").

                                   WITNESSETH

         WHEREAS, the Parent Company on behalf of itself and any of its
subsidiaries which entered into that certain Employment Agreement by and between
the Parent Company and certain un-named subsidiaries and the Employee, first
effective as of August 1, 2001 (the "Employment Agreement");

         WHEREAS, the Parent Company is a holding company that operates through
its subsidiary entities, including, but not limited to, the Subsidiary Company;

         WHEREAS, the Employee is employed by and primarily performs services
for the Subsidiary Company, and from time to time, performs services for the
benefit of the Parent Company and its other subsidiaries;

         WHEREAS, the parties hereto are now desirous of clarifying the
relationship as regards to the Employment Agreement, clearly identifying the
contractual parties thereto and it is the intent of the Subsidiary Company to
continue to employ the Employee on the same terms and conditions as set forth in
the Employment Agreement;

         WHEREAS, the Parent Company, the Subsidiary Company and the Employee
now desire to confirm and clarify in the Employment Agreement that Employee is
employed by the Subsidiary Company and the Subsidiary Company now desires to
accept and assume the assignment of the financial obligations and any and all
other obligations of the Parent Company arising under the Employment Agreement;

         NOW, THEREFORE, for and in consideration of the premises, and other
good and valuable consideration, including the assignment of the financial
obligations and any and all other obligations of the Parent Company pursuant to
the Employment Agreement, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

         1.       NOVATION. The Parent Company and the Subsidiary Company hereby
agree to substitute the Subsidiary Company as a party to the Employment
Agreement, in place of and substitution for, the Parent Company.

         2.       ACCEPTANCE. The Subsidiary Company hereby agrees to the
substitution, assumes and agrees to pay, perform and discharge in due course any
and all financial and other

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obligations and other liabilities of the Parent Company arising under the
Employment Agreement, subject to the provisions of the Employment Agreement.

         3.       EMPLOYEE. The Employee hereby consents to the substitution of
the Subsidiary Company for the Parent Company under the Employment Agreement
pursuant to the terms, conditions and capacities set forth in the Employment
Agreement. Further, the Employee hereby confirms and affirmatively agrees to
remain bound by the Employment Agreement in accordance with the terms and
conditions thereunder and that Employee's rights and obligations, including, but
not limited to, the benefits described therein and the applicable effective
dates set forth in the Employment Agreement shall remain in full force and
effect.

         4.       SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon,
inure to the benefit of and be enforceable by and against the respective
successors and assigns of the Parent Company and the Subsidiary Company.

         5.       RELEASE. The Subsidiary Company and the Employee hereby
release, acquit and forever discharge the Parent Company of and from all
obligations and other liabilities of any kind or character, whether known or
unknown, liquidated or unliquidated, fixed or contingent, formerly existing, now
existing or that might arise hereafter, under the Employment Agreement.

         6.       GOVERNING LAW. This Agreement is being made and executed in
and is intended to be performed in the State of Texas and shall be governed,
construed, interpreted and enforced in accordance with the substantive laws of
the State of Texas, to the exclusion of any laws, substantive or otherwise which
would direct the law of any other jurisdiction to be applicable hereto.

         IN WITNESS WHEREOF, each of the parties hereto has executed this
Agreement as of the dates set forth below in multiple counterparts, each of
which shall be deemed an original, to be effective as of the date first set
forth above.

GRANT GEOPHYSICAL, INC.                        GRANT GEOPHYSICAL (INT'L), INC.

By: /s/ RICHARD F. MILES                       By: /s/ A. MARIZZA GLANCEY
    -------------------------------                -----------------------------
    Richard F. Miles                               A. Marizza Glancey
Its: President and CEO                         Its: Corporate Secretary

Date: March 21, 2003                           Date: March 21, 2003

EMPLOYEE

/s/ RICHARD J. DUNLOP
------------------------------------
Richard J. Dunlop

Date: 21st March, 2003
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